Due to its highly corrosion-resistant nature, the requirement to provide a hygienic environment for both liquids and air service to a process will often involve sanitary stainless steel. The industries that demand a sterile microbiological-free system can be found in Aerospace, Semi-Conductor, Food & Beverage, Pharmaceutical and Personal Care. Some facilities, such as Nuclear and other power generating plants may not have the same need for a biological free environment but require the other benefits found in a sanitary stainless-steel system, such as the durability of the steel.
Sanitary Stainless steel piping systems typically have welded joints with elongated bends and are so designed so that there is a smooth transition from section to section and, therefore, contaminants cannot accumulate. The welds need to be smooth and have full penetration inside and precautions must be made to prevent oxidation during welding. Most Sanitary Stainless-Steel systems use a grade of steel that is either 304 or 316. This type of steel contains Chromium Oxide which protects the sheets or piping components from corrosion or contamination. Welding processes that keep a consistent temperature and exhibit a lower heat input will help maintain the proper amount of Chromium in the steel. Inert gases such as Argon or Helium are commonly used to create this type of welding condition. Orbital welding systems are very precise and reliable due to their speed, consistency and ability to perform most welding in a sterile environment with limited human involvement.
Borescope testing (fiber optics) is frequently required on sanitary stainless steel piping to insure that the interior welds on the piping can be visually seen and confirm that there is a smooth surface with no pits, cracks or areas where contaminants could accumulate. Passivation or pickling can additionally be performed if further hygienic cleaning of the pipe is required.
Discoloration around the welds is often a good indicator of potential corrosion hazards in a sanitary stainless-steel system and should be kept to a minimum or eliminated.
The fabrication and installation of sanitary stainless-steel piping, fittings, valves and equipment requires a contractor’s commitment to extreme quality assurance, proper documentation, verifiable traceability of materials and the ability to provide assistance to the facility during commissioning and start up. Waco has trained welders who are practiced at sanitary stainless steel welding processes. We have a trained QA/ QC staff that keeps updated on current requirements and certifications. We have a quality system in place that streamlines the entire process from design to product delivery.
Water Treatment and Wastewater Treatment processes are significantly different from each other. This article will explain both and demonstrate some of the differences.
Water Treatment systems are typically designed to take fresh water from a body of water, well or aquifer to a storage tank. Filters systems in combination with flocculant clarifiers and/or coagulants are used to remove sedimentation. Biocides and chlorine treatment may be added to control bacteria and biological microbes. Additional chemicals may be added to balance PH levels.
Wastewater processes, on the other hand, require extensive additional treatment, which involves screening, filtration, aeration and chemical additive equipment. There has been significant new technology involving optimization of the treatment process for both of the solid and liquid components in Wastewater systems.
Waco has been on the forefront of correctly implementing these new engineered designs. The combination of advanced technology and Waco’s construction expertise has provided vitally important environmental improvements to both Water and Wastewater treatment systems. These are the challenges facing today’s growing municipalities, counties and industrial manufacturers charged with Water and Wastewater facility management. We will explain what systems Waco currently constructs and how this is benefiting our communities, parks, waterways and wildlife management areas.
Fresh Water – Pump Stations: These facilities are typically installed to increase the amount of water required for a certain municipality or county’s system. Most require a large holding tank of fresh water, large pumps and a piping system. Typically, Pump Stations receive water that has previously been treated. In some cases, chlorine might be added or additional chemical treatment for ph control may be required. The main function of a Pump Station is to maintain water pressure and water capacity.
Waco has installed many of these Pump Stations throughout Virginia and has a solid reputation for competitively bidding and completing this work ahead of schedule. We have a dedicated team that works exclusively on these types of projects. We understand the means and methods used to install the equipment and ensure the proper scheduling of the work. We understand the construction process, how to properly install the equipment and schedule the work. We can foresee potential problems and bring them to the attention of the owner before they delay the project or incur additional expense. We have warehouse facilities capable of storing long lead time parts and equipment, further maintaining our ability to keep the project on schedule.
Waste Water Treatment
Types of Water & Wastewater Treatment Facilities being constructed
Odor Control Stations
Municipal Wastewater Treatment Plants
Industrial Onsite Wastewater Treatment Facilities
Odor Control Stations:
Sewage treatment facilities can be located in densely populated areas. It is critical that the facility operates with the least amount of released odors as possible. Odor control is performed with many methods, but the most commonly used is a Bio-Scrubber system. This system gathers vapors from the wet well using industrial fans, and adds chemicals and water to the vapors which are then sent through a bio filter system. These tanks and filters collect enough of the hydrogen sulfide gas so that any discharge out the stack has a minimal amount of odor.
Municipal Wastewater Treatment Facility
Main processes for cleaning Wastewater
Physical – This involves large screens, centrifuges, clarifiers, aeration or blower air, Nano membranes or filter media types and reverse osmosis.
Chemical – This involves treating the water with chemicals such as lime, bleach/chlorine, hypochlorite, ozone or several other types of disinfectant.
Biological – naturally occurring microbes or organic matter that breaks down the pathogens or wastes into components that can be further treated with less chemicals required. Anaerobic Digestion process.
Newer Technologies – UV Light
Goal: To separate the solids from the liquids
Liquids typically go through a multi stage filtering and aeration process. Chemicals are added along the way until the wastewater is considered fresh potable water and suitable for discharge back into the environment.
Solids will go through a more involved filter pressing and heating process to drive more liquid out of the solid and make it into what is commonly called a “cake”. Once it gets to this stage it is a biosolid or sewage sludge. An anaerobic digestion process uses naturally occurring bacteria to convert organic matter (sewage sludge) into methane and carbon dioxide. These components methane and CO2 are often referred to as Biogas. The methane can be burned off using a thermal oxidizer, or it can be used in a combustion process to convert to a useful energy source for operating segments of the Wastewater Treatment facility.
The biosolids are further chemically treated until the level of pathogens has been reduced to an allowable limit set by EPA and other agencies. This final product (ammonia/nitrogen rich solids) can then either be used on soils for agricultural purposes or for reclamation sites or landfill cover. The current breakdown of biosolids application in the US is – Agricultural – 42%, Landfill or reclamation soil – 43%, and Incineration – 15%
Industrial Onsite Wastewater Treatment Facilities
Many industrial manufacturers are required to pre-treat their chemical discharge before sending it to a municipal or county wastewater treatment plant. Waco’s long history of experience working in industrial plants and our combined wastewater capabilities allow us to provide a combined approach that many other contractors cannot offer.
Waco has the ability to perform major upgrades to existing operational wastewater treatment facilities. We have an extensive completed project list and over 40 years of experience in this segment of the construction business. Our jobs range from minor equipment change outs of $50,000 to large $10 million to $18 million projects involving installation of entire new buildings with filtering and chemical processing equipment. We specialize in increasing the capacity of a wastewater treatment facility, or constructing components to bring an existing facility into compliance with new water regulation codes, or for reissuance of permits, such as the Virginia Pollution Discharge Elimination System (VPDES).
All this work can be done while the facility is operating. Coordinating with plant operators and engineers is critical, especially when the final connections between the older system components are made with newly installed systems. Other factors such as stormwater control measures and modifications to roadways are elements that must be considered before implementation of any construction process.
Water and Wastewater treatment facilities will continue to see increasing demands. Waco incorporates these new technologies into the project, and has the ability to implement those requirements in a coordinated construction process. We work with the top Water and Wastewater treatment engineering firms, and invite you to review our past projects or contact a reference from our extensive list of clients.